Happy Accidents and Confusing Chemistry

After the exciting delivery of some new Kemtex colours and picking up some new ideas at Wonderwool, I have been eagerly awaiting the chance to dye some more silk. I normally paint the silk in a relatively random fashion but I wanted to try something a little more sensible and to have a go at making some colour gradients.

I spent the morning remaking all my old dye stock solutions and making up my new colours as well. Previously, I had been using white vinegar as my fixing agent but I wanted to try using citric acid and adding some urea. The purpose of urea is to increase the solubility of the dyes (therefore allowing you to make higher concentrations) for brighter, more intense colours as well as helping to keep the fibre moist, particularly during the fixing stage.

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It was while making up the dye stock solutions that I made a mistake I wouldn’t realise until much later… I made up approximately 5 % dye solutions, added the citric acid and the same amount of what I thought was urea, as recommended in the Kemtex instructions. I’ve heard a lot of people saying they use 2 % concentration dyes for painting and 1 % for immersion dyeing but I have never found concentrations that low give me quite the colour I wanted, hence the higher concentrations.

Counterintuitively enough, most chemical dyes are actually not very water soluble. Certain dyes, Kemtex Black for example, are notorious for being difficult to fully dissolve. This is problematic because unless you want to start filtering your solutions, undissolved dye means you have no idea what the concentration of your solution is and makes it difficult to get predictable, repeatable results as well. I’ll talk a bit more about the chemistry of all this later but back to playing with colour…

I gave the silk a rinse in cool water before I left it to soak overnight in water with a lot of citric acid added. The silk I have isn’t pre-treated and the previous batches have been really clean so I didn’t worry about scouring it thoroughly. I made sure the silk was relatively dry before I start applying the dye, as I didn’t want any additional dilution of the dyes.

After the poor results with the black from my last set of silk dyeing, I was keen to see if the combination of citric acid and more concentrated solutions would fix this, so I started with some pure black in the corner trying to work through dark to light purples before going to magenta/pink at the end.

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Silk Drying

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My handpainted silks are finally dry! As you can see from comparison to the photos from the other post, some of the colours, particularly ones I’ve mixed myself, aren’t as intense as they were when the silk was still wet. However, some sections, particularly the red and green/yellow silks have come out with exactly the kind of colour saturation and intensity I was looking for. Lots of dye and aggressive mashing of the fibres seems to be the trick with handpainting. Thinning down the top beforehand did help but made it more difficult to handle, so I’m not sure it was worth it on reflection.

In general, I didn’t lose too much dye in the rising process but the turquoise sections took significantly more rinsing than any other colour. It’s remained a nice, saturated colour but I’m not sure if there’s something about that particular dye that meant it didn’t fix as well or maybe needed more vinegar in those areas.

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Yarn painting and silk

This Christmas, I treated myself to a rather sizeable delivery from World of Wool, including over half a kilo of lovely, mulberry silk. Unfortunately, I’ve not had much time to do much other than admire the packet but this weekend I fancied doing something a little less regimented than needlework and thought I’d have a go at some yarn painting.

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No such thing as too much silk!

One issue I’ve had with some of the yarn painting I’ve done is that the colours don’t always look as saturated or intense when the yarn is dry as they do during the dyeing process. I dyed the silk below using mostly greens with some black and mid-blues mixed in as well. Apparently adding a few drops of black can help the colours look more intense.

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Dyed silk top

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